This is a safety and efficacy trial of 2,3 dimercaptosuccinic acid (Chemet) of children with lead levels > or = 45 ugm/dl. All children with lead levels in that range are eligible. This is an open-label, multicenter trial sponsored by McNeil Consumer Products. Children are monitored weekly during 3 weeks of oral therapy and for 2 weeks after and then every 4-6 weeks for up to 6 months.